MRI features of the normal prostatic peripheral zone: the relationship between age and signal heterogeneity on T2WI, DWI, and DCE sequences

Funder: University of CambridgeAbstract: Objectives: To assess the multiparametric MRI (mpMRI) appearances of normal peripheral zone (PZ) across age groups in a biopsy-naïve population, where prostate cancer (PCa) was subsequently excluded, and propose a scoring system for background PZ changes. Methods: This retrospective study included 175 consecutive biopsy-naïve patients (40–74 years) referred with a suspicion of PCa, but with subsequent negative investigations. Patients were grouped by age into categories ≤ 54, 55–59, 60–64, and ≥ 65 years. MpMRI sequences (T2-weighted imaging [T2WI], diffusion-weighted imaging [DWI]/apparent diffusion coefficient [ADC], and dynamic contrast-enhanced imaging [DCE]) were independently evaluated by two uro-radiologists on a proposed 4-point grading scale for background change on each sequence, wherein score 1 mirrored PIRADS-1 change and score 4 represented diffuse background change. Peripheral zone T2WI signal intensity and ADC values were also analyzed for trends relating to age. Results: There was a negative correlation between age and assigned background PZ scores for each mpMRI sequence: T2WI: r = − 0.52, DWI: r = − 0.49, DCE: r = − 0.45, p < 0.001. Patients aged ≤ 54 years had mean scores of 3.0 (T2WI), 2.7 (DWI), and 3.1 (DCE), whilst patients ≥ 65 years had significantly lower mean scores of 1.7, 1.4, and 1.9, respectively. There was moderate inter-reader agreement for all scores (range κ = 0.43–0.58). Statistically significant positive correlations were found for age versus normalized T2WI signal intensity (r = 0.2, p = 0.009) and age versus ADC values (r = 0.33, p = 0.001). Conclusion: The normal PZ in younger patients (≤ 54 years) demonstrates significantly lower T2WI signal intensity, lower ADC values, and diffuse enhancement on DCE, which may hinder diagnostic interpretation in these patients. The proposed standardized PZ background scoring system may help convey the potential for diagnostic uncertainty to clinicians. Key Points: • Significant, positive correlations were found between increasing age and higher normalized T2-weighted signal intensity and mean ADC values of the prostatic peripheral zone. • Younger men exhibit lower T2-weighted imaging signal intensity, lower ADC values, and diffuse enhancement on dynamic contrast-enhanced imaging, which may hinder MRI interpretation. • A scoring system is proposed which aims towards a standardized assessment of the normal background PZ. This may help convey the potential for diagnostic uncertainty to clinicians

Validation of SPARCC MRI-RETIC e-tools for increasing scoring proficiency of MRI sacroiliac joint lesions in axial spondyloarthritis

BACKGROUND The Spondyloarthritis Research Consortium of Canada (SPARCC) developers have created web-based calibration modules for the SPARCC MRI sacroiliac joint (SIJ) scoring methods. We aimed to test the impact of applying these e-modules on the feasibility and reliability of these methods. METHODS The SPARCC-SIJ $_{RETIC}$ e-modules contain cases with baseline and follow-up scans and an online scoring interface. Visual real-time feedback regarding concordance/discordance of scoring with expert readers is provided by a colour-coding scheme. Reliability is assessed in real time by intraclass correlation coefficient (ICC), cases being scored until ICC targets are attained. Participating readers (n=17) from the EuroSpA Imaging project were randomised to one of two reader calibration strategies that each comprised three stages. Baseline and follow-up scans from 25 cases were scored after each stage was completed. Reliability was compared with a SPARCC developer, and the System Usability Scale (SUS) assessed feasibility. RESULTS The reliability of readers for scoring bone marrow oedema was high after the first stage of calibration, and only minor improvement was noted following the use of the inflammation module. Greater enhancement of reader reliability was evident after the use of the structural module and was most consistently evident for the scoring of erosion (ICC status/change: stage 1 (0.42/0.20) to stage 3 (0.50/0.38)) and backfill (ICC status/change: stage 1 (0.51/0.19) to stage 3 (0.69/0.41)). The feasibility of both e-modules was evident by high SUS scores. CONCLUSION The SPARCC-SIJ $_{RETIC}$ e-modules are feasible, effective knowledge transfer tools, and their use is recommended before using the SPARCC methods for clinical research and tria

Late complication of a renal calculus: fistulisation to the psoas muscle, skin and bronchi

ABSTRACTKidney disease presenting with cutaneous fistula is a rare condition. We present a case of a 90-year-old woman with dementia who had no prior urological problems and had a cutaneous fistula in the left lumbar region. A fistulogram and computer tomography examination revealed a large staghorn calculus with signs of xanthogranulomatous pyelonephritis in the left kidney and renal fistulisation to the psoas muscle, skin and bronchi. To our knowledge this is the first report in the literature of coexisting renal fistulisation to the psoas major muscle, skin and bronchi. This report illustrates how computed tomography in combination with fistulography can resolve the diagnostic dilemma that pertains to the complex spread of the disease in cases involving nephrocutaneous fistula. Furthermore, the report shows how a renal calculus, even asymptomatic, can cause a serious medical condition, and highlights the importance of early medical intervention

Three-dimensional MRI evaluation of the effect of bladder volume on prostate translocation and distortion

The accuracy of any radiation therapy delivery is limited by target organ translocation and distortion. Bladder filling is one of the recognised factors affecting prostate translocation and distortion. The purpose of our study was to evaluate the effect of bladder volume on prostate translocation and distortion by using detailed three-dimensional prostate delineation on MRI

Three-dimensional MRI evaluation of the effect of bladder volume on prostate translocation and distortion.

Background The accuracy of any radiation therapy delivery is limited by target organ translocation and distortion. Bladder filling is one of the recognised factors affecting prostate translocation and distortion. The purpose of our study was to evaluate the effect of bladder volume on prostate translocation and distortion by using detailed three-dimensional prostate delineation on MRI. Patients and methods Fifteen healthy male volunteers were recruited in this prospective, institutional review board-approved study. Each volunteer underwent 4 different drinking preparations prior to imaging, with MR images acquired pre- and post-void. MR images were co-registered by using bony landmarks and three-dimensional contouring was performed in order to assess the degree of prostate translocation and distortion. According to changes in bladder or rectum distention, subdivisions were made into bladder and rectal groups. Studies with concomitant change in both bladder and rectal volume were excluded. Results Forty studies were included in the bladder volume study group and 8 in the rectal volume study group. The differences in rectal volumes yielded higher levels of translocation (p < 0.01) and distortion (p = 0.02) than differences in bladder volume. Moderate correlation of prostate translocation with bladder filling was shown (r = 0.64, p < 0.01). There was no important prostate translocation when bladder volume change was < 2-fold (p < 0.01). Moderate correlation of prostate distortion with bladder filling was shown (r = 0.61, p < 0.01). Conclusions Bladder volume has a minimal effect on prostate translocation and effect on prostate distortion is negligible. Prostate translocation may be minimalised if there is < 2-fold increase in the bladder volume.The authors acknowledge grant support from the Royal College of Radiologists UK and research support from Cancer Research UK, National Institute of Health Research Cambridge Biomedical Research Centre, Cancer Research UK and the Engineering and Physical Sciences Research Council Imaging Centre in Cambridge and Manchester and the Cambridge Experimental Cancer Medicine Centre

Assessment of short-term effect of platelet-rich plasma treatment of tendinosis using texture analysis of ultrasound images

Computer-aided diagnosis (i.e., texture analyses) tools are becoming increasingly beneficial methods to monitor subtle tissue changes. The aim of this pilot study was to investigate short-term effect of platelet rich plasma (PRP) treatment in supraspinatus and common extensor of the forearm tendinosis by using texture analysis of ultrasound (US) images as well as by clinical questionnaires

Evaluation of cross sections for fast ion reactions with beryllium in helium and hydrogen fusion plasmas

To computationally support hydrogen and helium plasma discharges in the early stages of tokamak operation and to support the commissioning of the neutron detectors during these operational phases, creation of a realistic neutron and gamma ray particle source for Monte Carlo simulations will be needed. One of the most important parts of creating the particle source is calculating the reaction rates of the particle-emitting reactions to determine the emission profile in the plasma and the energy spectra of the emitted particles. In this paper the analysis and evaluation of cross sections for important neutron-emitting reactions, namely, 9Be(p,nγ)9B, 9Be(3He,nγ)11C, and charged-particle emission reactions 9Be(p,d)2α and 9Be(p,α)6Li that cause neutron emission in the next step of interactions are presented. The reaction cross sections were evaluated based on experimental measurements and empirical models describing the interaction of two charged particles. Evaluation of the associated uncertainties was also performed. The main goal of the work is to propose the newly evaluated cross sections for inclusion in the FENDL nuclear data library, thus making the cross section available to other researchers studying the above listed reactions

Multiphysics approach to plasma neutron source modelling at the JET tokamak

A novel multiphysics methodology for the computation of realistic plasma neutron sources has been developed. The method is based on state-of-the-art plasma transport and neutron spectrum calculations, coupled with a Monte Carlo neutron transport code, bridging the gap between plasma physics and neutronics. In the paper two JET neutronics tokamak models are used to demonstrate the application of the developed plasma neutron sources and validate them. Diagnostic data for the record JET D discharge 92436 are used as input for the TRANSP code, modelling neutron emission in two external plasma heating scenarios, namely using only neutral beam injection and a combination of the latter and ion cyclotron resonance heating. Neutron spectra, based on plasma transport results, are computed using the DRESS code. The developed PLANET code package is employed to generate plasma neutron source descriptions and couple them with the MCNP code. The effects of using the developed sources in neutron transport calculations on the response of JET neutron diagnostic systems is studied and compared to the results obtained with a generic plasma neutron source. It is shown that, although there are significant differences in the emissivity profiles, spectra shape and anisotropy between the neutron sources, the integral response of the time-resolved ex-vessel neutron detectors is largely insensitive to source changes, with major relative deviations of up to several percent. However it is calculated that, due to the broadening of neutron spectra as a consequence of external plasma heating, larger differences may occur in activation of materials which have threshold reactions located at DD neutron peak energies. The PLANET plasma neutron source computational methodology is demonstrated to be suitable for detailed neutron source effect studies on JET during DT experiments and can be applied to ITER analyses

Diagnostic accuracy of haemophilia early arthropathy detection with ultrasound (HEAD-US): a comparative magnetic resonance imaging (MRI) study

Repeated haemarthroses affect approximately 90% of patients with severe haemophilia and lead to progressive arthropathy, which is the main cause of morbidity in these patients. Diagnostic imaging can detect even subclinical arthropathy changes and may impact prophylactic treatment. Magnetic resonance imagining (MRI) is generally the gold standard tool for precise evaluation of joints, but it is not easily feasible in regular follow-up of patients with haemophilia. The development of the standardized ultrasound (US) protocol for detection of early changes in haemophilic arthropathy (HEAD-US) opened new perspectives in the use of US in management of these patients. The HEAD-US protocol enables quick evaluation of the six mostly affected joints in a single study. The aim of this prospective study was to determine the diagnostic accuracy of the HEAD-US protocol for the detection and quantification of haemophilic arthropathy in comparison to the MRI